It is not uncommon to integrate new network topologies into an existing cellular network in order to support different modes of communications and accommodate different applications. One example of the integrated network is the heterogeneous network combining macros, micros, picos, femtos and relay network technologies into a long-term evolution (LTE) or LTE-advanced (LTE-A) network all sharing the same frequency spectrum. Another example is to allow device to device (D2D) communication between two cellular user equipments (UEs) operating in the cellular system when the communicating UEs are sufficiently close to each other to use the cellular radio resources in an efficient manner. As an application example of the D2D UEs integrated into a cellular network, the D2D communication may take on characteristics of machine-to-machine (M2M) communication where the machines communicate directly with each other under supervision of a cellular network, sharing the radio resources with cellular users.